Bezoars are any of several types of solid or semi-solid masses of indigestible material found in the stomach of humans and many animals including cattle, cats, rats, rabbits, and non-primates. Trichobezoars, which contain a mesh of ingested hair, are known to entrap undigested dietary fat in the hair mesh. The terms bezoars, trichobezoars, and hairballs will be used interchangeably throughout this application. While the incidence of bezoars is generally very low in humans, a somewhat greater risk exists among mentally or emotionally challenged children, particularly humans who habitually pluck their hair (trichotillomania) and/or eat their hair (trichopagia).
Animals that constantly groom themselves, such as cats and rabbits, regularly ingest large quantities of hair. Normally, the ingested hair passes through the gastrointestinal tract of the animal and is excreted in the feces. However, the ingestion of large quantities of hair may cause the hair to accumulate in the stomach and form a hairball or trichobezoar. A hairball is typically composed of hair, mucous, water, food particles and mineral salts. Any ingested hair that is not digested or does not otherwise pass down the digestive tract may accumulate in the stomach and form an over hairball. The most common physiological consequences thereof are diarrhea and vomiting. A hairball can be harmful to the animal if it impedes the normal digestive process by blocking the pylorus and preventing the passage of digesta down the gastrointestinal tract. More frequently, hairballs are nothing more than a nuisance to the animal and its owner. For example, the cat will attempt to eliminate the hairball from the stomach through the vomiting reflex. A hairball may produce constipation and defecation difficulties if it passes from the stomach and becomes lodged in the lower bowel.
Approaches to the treatment of hairballs have included administration of compositions and foods comprising fiber supplements, fat emulsifiers, lubricants, malt syrup emulsion, mineral oil, petrolatum, and proteolytic enzymes (bromelain). However, there remains a need for methods and compositions for the treatment and/or prevention of hairballs in mammals in need thereof and, in particular, there remains a need for methods and compositions for the treatment and/or prevention of hairballs in non-human animals, including companion animals, e.g., cats and dogs.